This invention relates to apparatus for handling units of currency. The invention will be described mainly in the context of coin handling, but is also applicable to apparatus which also or alternatively handles other units of currency, such as banknotes or the like.
It is known to provide a coin handling apparatus which receives and validates coins of different denominations, and directs valid coins to respective containers each containing coins of a single denomination. It is also known to dispense coins from these containers as change in an amount corresponding to the difference between the value of inserted coins and the price of a product or service obtained from a machine associated with the coin handling apparatus.
Such coin handling apparatus is typically provided in vending machines or payphones, which are required to operate unattended for long periods of time. Typically, power is supplied to the coin handling apparatus from the machine within which it is located, although some currency handling apparatus has mains supply ports.
In either case, the voltage supplied to the apparatus (and hence the power available to it) may differ from the voltage level it requires for normal operation. For example, European mains power nominal supply levels vary at present between 240-220 volts, and may in future be set with a relatively wide tolerance. Thus, the voltage may vary according to the location of the apparatus. Equally, the voltage may vary over time, since in some areas voltages are reduced at peak usage periods.
It may be dangerous for a currency handling apparatus to operate at an inadequate power level. For example, the operation of the currency receiving and accepting system, or of the currency dispensing system, may cause jams if inadequate power is available to operate the electro mechanical actuators (solenoids or motors) required. Such jams are costly, and may cause significant loss of revenue if the apparatus is put out of action.
It would be possible to detect an unacceptably low power supply level and suspend operation of the apparatus until power returned. However, whilst this would prevent jams, it would be ineffective in reducing lost revenue, and in dealing with geographical voltage variations.
At this point, it may be mentioned that various techniques are known for preventing jams on power loss; for example, our earlier British patent GB 2246898 discloses a coin validator which has an auxiliary power supply (for example a capacitor) with sufficient power to keep the coin acceptor gate in operation, when power is lost, until any coins in the validator have passed through the gate.
Similarly, FR 2355418 discloses a coin operated telephone with a non-volatile credit memory, with a capacitor which may also supply energy to a rocker within a coin refund mechanism, in the event of power failure.
Furthermore, our earlier application U.S. Pat. No. 4,979,208 shows a coin mechanism for a payphone in which a low power mode is provided for open switch intervals, during which machine operating parameters are saved in a capacitor-backed memory to enable operation to resume after the end of the open switch interval. During the interval, however, operation of the mechanism is interrupted.
Alternative techniques attempt to reduce the overall power consumed by a currency handling apparatus, for example to enable it to be used with a battery or to be powered from a telephone line. Examples are the use of arrival sensors to power up the mechanism only on arrival of a coin, as described in our earlier applications GB 2094008 and EP 0184393.
A vending machine which reduces average power used by, for example, its heating and cooling devices during periods of the day when an office is closed (which do not apparently coincide with reduced supply power conditions) is disclosed in U.S. Pat. No. 5,868,274.
By way of contrast, the present invention provides a currency handling apparatus which can sense the probable occurrence of a reduced power condition, and which can, in response, continue to operate in a selected reduced power mode, in which its currency handling functions are still performed.
In an implementation, it is the power during periods of peak power use by the apparatus, rather than the long-term average power, which is reduced in such modes.
For example, the reduced power mode may provide one or more modes of operating a currency dispensing subsystem at reduced power. Where a plurality of actuators (e.g. motors) are normally employed simultaneously for dispensing, in the reduced power mode they may sequentially be activated instead. Further, power to peripheral devices not directly concerned with the transport or handling of currency (such as displays) may be reduced or interrupted, either during a currency handling operation or permanently.
Where a reservoir (such as a capacitor) of power is provided, which may be recharged from the external power supply, then the reduced power mode may involve the provision of a predetermined delay between successive operations of power-consuming components, the delay being sufficient to permit at least some substantial re-charging of the reservoir.
For example, a delay may be provided between successive operations of electro mechanical currency handling actuators (such as solenoids driving the accept gate and separator gates of a currency acceptor, and/or the dispense motors or dispense solenoids of a change dispenser). A delay may be provided between successive actuations of the same device, or between successive actions of any such device.
At this point it may be mentioned that the control of the duration of the period between successive operations of a coin accept gate is disclosed, for a very different purpose, in GB 2137793.
Other aspects and preferred embodiments of the invention, with corresponding advantages, will be apparent from the following description and claims.